In 3GPP (Third Generation Partnership Project) network systems service based control such as charging control and QoS (Quality of Service) control is becoming standardized. For service based charging control, a Charging Rules Function (CRF) is introduced to the 3GPP reference architecture. For service based QoS control, a Policy Decision Function (PDF) is introduced to the 3GPP reference architecture.
Both the CRF and PDF interface with an Application Function (AF) to get application session and media component information to be used for rule creation, i.e. the CRF uses the application session and media component information for charging rule creation, and the PDF uses the application session and media component information for QoS rule creation. The AF sends information about the application session and media component(s) both to the CRF and PDF including e.g. information on a filter of a media component and a service in question (e.g. Application Id and/or Media Type).
Both the CRF and PDF interface with a Gateway (GW) to give rules to the GW which enforces the rules.
One key principle for enhancing the performance of a core network is to maximize the usage of service management and to minimize the usage of service control signaling. This means that as much as possible information is pre-configured in network elements and service control signaling is used only when absolutely necessary.
Rules (e.g. charging or QoS rules) pre-configured in the GW are used if possible, because this way, it is possible to decrease the amount of service control signaling traffic.
If the filter of an application session component is dynamic, the GW gets the filter from the AF through a service based control entity such as the CRF and PDF. With the filter, the GW can identify a service flow.
However, the GW is not able to apply pre-configured service specific rules in case of receiving dynamic information from the AF through the service based control entity.